We started out with 70 some odd chicks, the same age and of 11 different breeds. We already had some adult hens so we put some of the chicks in with the hens because they had hatched out some eggs the same day these chicks arrived. We thought it would be funny to see a bantam Cochin raising a Jersey Giant and standard Cochins. And they are funny but the chicks with the adults were free ranged all day, cooped at night and had full access to the chick feed at all times while the other chicks were never allowed free range, only cooped and fed the same chick feed. The fully cooped chicks are much, much bigger and better feathered out, too! Free range may be good for some things but it sure slowed the growth on the breeds of chicks from the same hatcheries. We now let everyone free range but the cooped chicks run back to the coop at the slightest little noise or bird that flies over. They are so much fun to watch.